A stereotaxic method based on ventricular radiography in the cat (with special reference to the stereotaxic topography of the substantia nigra).

A method based on an intracerebral coordinate system and contrast ventriculography was developed for stereotaxic surgery in the cat. The intercommissural (CA-CP) line was used as the principal reference because its length showed little variability in animals within a wide weight range. The stereotaxic coordinates of the substantia nigra (SN) in relation to the CA-CP line and the midline were evaluated in serail sections. Stereotaxic operations with the use of ventricular radiography were performed in different parts of the SN in 18 cats. Histological verification showed that the selected target regions within the SN were very accurately reached in all animals operated with this method. The precision of the stereotaxic method based on the intracerebral coordinate system compared to the Horsley-clarke method is discussed.